Among the vaccines currently used in India's Universal Immunization Programme, which one is the MOST heat stable, permitting the longest storage outside the cold chain without significant potency loss?
- A Hepatitis B vaccine ✓
- B Measles-rubella vaccine
- C BCG vaccine
- D Oral polio vaccine
Correct answer: A. Hepatitis B vaccine
Explanation
Hepatitis B vaccine, being an adsorbed recombinant product, withstands heat exposure best and retains potency for months even at 30 to 37 degrees Celsius. OPV is the most heat labile vaccine in the programme and loses potency rapidly outside refrigeration, which is why it anchors the coldest point of the chain. MR and BCG are live attenuated products of intermediate heat sensitivity.
Reference: Park's Textbook of Preventive and Social Medicine, 25th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.